A typical nail stapler includes a magazine for storing nails, a nozzle and a hammering device for driving the nails from the magazine through the nozzle one at a time. There is a certain nail stapler that includes a hammering device capable of hammering a nail many times until it hammers the nail into an object completely. It, however, quite often occurs that when hammering the nail the second or third time, the hammering device hammers the next nail by mistake. This hammering by mistake causes a jam in the nozzle. To clear the jam and reload the nails is troublesome.
The present invention is therefore intended to obviate or at least alleviate the problems encountered in the prior art.